IB/mlx5: Report correctly tag matching rendezvous capability

commit 89705e92 upstream.

Userspace expects the IB_TM_CAP_RC bit to indicate that the device
supports RC transport tag matching with rendezvous offload. However the
firmware splits this into two capabilities for eager and rendezvous tag
matching.

Only if the FW supports both modes should userspace be told the tag
matching capability is available.

Cc: <stable@vger.kernel.org> # 4.13
Fixes: eb761894 ("IB/mlx5: Fill XRQ capabilities")
Signed-off-by: Danit Goldberg <danitg@mellanox.com>
Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/infiniband/hw/mlx5/main.c

@@ -939,15 +939,19 @@ static int mlx5_ib_query_device(struct ib_device *ibdev,
 	}
 
 	if (MLX5_CAP_GEN(mdev, tag_matching)) {
-		props->tm_caps.max_rndv_hdr_size = MLX5_TM_MAX_RNDV_MSG_SIZE;
 		props->tm_caps.max_num_tags =
 			(1 << MLX5_CAP_GEN(mdev, log_tag_matching_list_sz)) - 1;
-		props->tm_caps.flags = IB_TM_CAP_RC;
 		props->tm_caps.max_ops =
 			1 << MLX5_CAP_GEN(mdev, log_max_qp_sz);
 		props->tm_caps.max_sge = MLX5_TM_MAX_SGE;
 	}
 
+	if (MLX5_CAP_GEN(mdev, tag_matching) &&
+	    MLX5_CAP_GEN(mdev, rndv_offload_rc)) {
+		props->tm_caps.flags = IB_TM_CAP_RNDV_RC;
+		props->tm_caps.max_rndv_hdr_size = MLX5_TM_MAX_RNDV_MSG_SIZE;
+	}
+
 	if (MLX5_CAP_GEN(dev->mdev, cq_moderation)) {
 		props->cq_caps.max_cq_moderation_count =
 						MLX5_MAX_CQ_COUNT;

include/rdma/ib_verbs.h

@@ -290,8 +290,8 @@ struct ib_rss_caps {
 };
 
 enum ib_tm_cap_flags {
-	/*  Support tag matching on RC transport */
-	IB_TM_CAP_RC		    = 1 << 0,
+	/*  Support tag matching with rendezvous offload for RC transport */
+	IB_TM_CAP_RNDV_RC = 1 << 0,
 };
 
 struct ib_tm_caps {